Illuminating-tile.



No. 871,793. PATENTED NOV. 26, 1907. J. B. FRENCH.

ILLUMINATING TILE.

APPLICATION mum mm 19, 1906.

JAMES BARRETT FRENCH, OF CHICAGO, ILLINOIS.

ILLUMINATING-TILE Specification of Letters Patent.

Patented Nov. 26, 1907.

Application filed May 19, 1906. Serial No. 317,714.

To all whom it may concern:

Be it known that I, JAMES BARRETT FRENCH, a citizen of the United Statesof America, and a resident of Chicago, in the county of Cook and Stateof Illinois, have invented certain new and useful Improvements inIlluminating-Tiles, of which the following is a specification.

The main objects of this invention are to provide an improved form ofilluminating tile for floors and sidewalks, in which each light of glasswill be individually surrounded by a friction surface which is firmlyheld in the metal framework, and which is not likely to have piecesthereof chipped off or broken out as is the case when the friction metalmerely forms. an inlay in the cement, or loosely rests in the metalframe or is interposed so as to bear both against the metal frame andthe light; and to provide a strong and safe tile of this class having alarge proportion of illuminating surface and friction surface. Iaccomplish these objects by the device shown in the accompanyingdrawings, in which:

Figure 1 is a top plan, partly broken away, of an illuminating tileconstructed according to my invention. Fig. 2 is an enlarged transversesection of the same on the line 22 of Fig. 1, also partly broken away.

In the construction shown in the drawings, the supporting frame orgrating 3 consists of a rectangular cast iron frame subdivided by meansof a plurality of integral intersecting cross-bars 4i and 5 forming aplurality of rectangular light apertures. Each of the light apertures issurrounded by an inwardly extending ledge or shoulder 7 near the lowersurface of the grating for supporting the lights of glass 6. Each lightof glass is preferably somewhat smaller than its individual frame andhas inclined sides. The lights are placed in their frames with theirlarge end downward. The inner bounding sides of the individual framesare inclined, the opening being widest at the top. The glass lights 6are securely fastened in their frames by means of a surrounding layer ofcement 8. This cement is adapted to yield, and rcvents the glass fromcracking on account 0 the unequal expansion of the glass and the metalof the grating, under changes of temperature. The upper surface of theside and end bars of the frame 3 and the upper surface of each of thecross-bars 4 and 5 is grooved, and said grooves are filled with lead 9which forms a strip or boundary of lead extending individually aroundeach light. This lead is softer than either the metal frame, the glasslights, or the surrounding cement, and has the wellknown property ofpreventing slipping and being safe to the tread of persons passing overthe same.

The grooves containing the lead filling 9, are made of larger diameterat the base. These grooves extend in continuous inter secting lines, asshown in Fig. 1. The metal framework will be cast with said grooves andthe lead will be poured into the same in a molten condition for formingthe continuous strips of lead or friction filling 9.

The glass, cement, and metal frames be come worn smooth by the passingof pedestrians, but each smooth surface is separated from the others bya strip of lead which prevents slipping as soon as the foot of thepedestrian comes in contact therewith. The cement which is used forsecuring the glass within the frames has the property of yielding andcompensating for strains on the glass due to unequal expansion. The sidebars and cross-bars of the grating are all integral with each other andall extend flush with the upper surface of the glass, so that in casethe cement surrounding any light of glass should become cracked for anyreason, the cracks will be confined to the particular band of cement.This prevents water from entering such cracks and causing them to extendover large areas of the grating as is the case where the filling betweenindividual lights is made entirely of cement at the upper surface, andis merely supported by a grating.

In the structure shown, the cement and hard metal of the frameworkpresented at the surface of the tile are of comparative small area. Thewidth of the layer or strip of cement used is merely sufficient toproperly hold the lights in the frame and to provide for the necessaryexpansion and yielding, to prevent the glass from cracking. The width ofthe metal frame presented at the surface is merely sullicient toproperly hold the friction filling 9, and to serve as a guard againstexcessive wear at the surface of the cement. This device thus presents astructure in which each individual glass light is entirely surroundedfirst by a comparatively narrow layer of cement, second by acomparatively narrow layer of hard metal and third by a comparativelywide layer of friction material such as lead, and in which both theglass and lead are firmly held in position by the shape of the adjoiningparts. The rectangular form of the lights and framework provides forusing a comparatively narrow layer or strip of cement.

What I claim as my invention and desire to secure by Letters Patent is:

An illuminating tile comprising a grating having straight, intersectingcross-bars inclosing light apertures and extending upward and providedwith ledges along their lower faces, lights supported by said ledges,spaced from said cross-bars and flush with the upper surfaces thereof, afilling of cement between each light and the surrounding parts of thegrating, said grating being provided with straight, intersecting groovesin the upper face thereof, said grooves being of increased width belowthe tops thereof, and a filling of soft metallic friction materialentirely filling said grooves and extending in straight, intersectinglines so as to completely surround each of said lights.

Signed at Chicago this 17th day of May,

JAlWES BARRETT FRENCH. Witnesses:

L. A. SMITH, WM. R. RUMMLER.

